1. Technical Field
The present invention relates to technology for eliminating air bubbles from a liquid located in a liquid supplying path inside a liquid ejecting apparatus or for suppressing generation of the air bubbles.
2. Related Art
In ink jet printers, there are cases where defective printing such as missing dots occurs when air bubbles are generated in ink located in an ink supplying path that is from an ink supply unit such as an ink cartridge to a record head. Thus, printers capable of eliminating the air bubbles (defoaming) from ink have been proposed (see JP-A-2006-75683).
In addition, in the ink jet printers, there are cases where defective printing such as missing dots occurs when the air bubbles are generated in the ink located in an ink supplying path that is from the ink supply unit such as an ink cartridge to a record head. Accordingly, to eliminate the air bubbles (defoaming) from the ink is needed. As a mechanism for performing such defoaming, a mechanism has been proposed in which a chamber (defoaming chamber) for capturing air bubbles by temporarily collecting the ink and a decompression chamber are located to be adjacent to each other through a partition wall having gas permeability and the air bubbles captured in the defoaming chamber are eliminated by adjusting the pressure of the decompression chamber to be lower than that of the defoaming chamber (see, JP-A-2006-95878).
In the ink jet printers, there are cases where a separate chamber for collecting ink is disposed in the ink supplying path in addition to the defoaming chamber used for a defoaming operation. As such a chamber, for example, there is a damper chamber that adjusts the internal pressure of the record head. There are cases where a flexible member is used in the damper chamber, and accordingly, there is a problem that air bubbles can be easily generated and grow. In addition, even in a configuration in which a sub tank is arranged in addition to a main tank used for storing ink, there are cases where air bubbles are generated in the sub tank.
However, sufficient consideration for a defoaming operation that is performed in a space (a broaden chamber) which has a cross-section area larger than that of the ink supplying path, such as the damper chamber or the sub tank has not been made. In addition, such problems may occur not only in the ink jet printers but also in a liquid ejecting apparatus that ejects any type of liquid such as lubricant or a resin liquid.